As mobile communication subscribers rapidly increase in number, service providers providing mobile communication services adopt a variety of additional services in order to attract customers and enhance quality of service for users, and provide an early media service, such as a ring back tone service, as one of such services.
The early media service is a service for providing media instead of a dial tone to an originating terminal, from a point when a call connection is tried until a connection is established and a communication is started, when a transmitting side places a call to a receiving side, i.e., the originating terminal tries a call connection to a subscriber number of the receiving side.
Such an early media service can function as means for representing an image or highlighting a characteristic of a receiving or transmitting subscriber. Therefore, instead of a ring back tone of a uniform mechanical tone conventionally provided to a service user, services that allow subscribers, particularly terminating subscribers, to change a ring back tone according to their tastes tends to be variously introduced recently. Such services are configured to output a ring back tone selected by a subscriber, instead of a conventional ring back tone, when a transmitter tries a communication.
However, although a variety of ring back tones based on the selection of a subscriber is provided instead of a conventional uniform ring back tone, media provided as a ring back tone are limited to audio data, such as a voice or music. Therefore, there is a limitation in fulfilling further higher desire of a user of a mobile communication terminal that can implement high quality audio and video owing to recent development of mobile communication terminal techniques.
In addition, the conventional early media service described above is a method using a circuit network, which has a problem in that due to the nature of the circuit network in which a circuit is exclusively used until a call connection is released, a circuit is exclusively used even when data is intermittently transmitted, and thus resources of the circuit is extremely wasted.
In addition, the conventional service method has a problem in that after an early service is provided, when the session is switched to another session to transmit and receive media to and from a counterpart terminal, the burden of a corresponding mobile communication terminal is heavy in the process of negotiating terminal capacity of a corresponding session and handling the session switch.
Accordingly, in providing an early media service, a variety of media for satisfying further higher desire of a user should be provided, together with a technique according thereto.